Spatial Distribution and Temporal Trends of Polycyclic Aromatic Hydrocarbons (PAHs) in Sediments from Lake Maryut, Alexandria, Egypt

Surface and core sediments from Lake Maryut, Egypt, one of the most polluted lakes in Egypt, were analyzed for polycyclic aromatic hydrocarbons (PAHs) using gas chromatography?Cmass spectrometry. This investigation represents the first extensive study of the distribution and sources of PAHs in sediments from Lake Maryut. The total PAHs concentrations (sum of 39 PAH compounds) in surface sediments varied greatly depending on the sampling location and ranged from 106 to 57,800 ng/g dry weight with a mean concentration of 6,950 ng/g. The most polluted areas are distributed in areas which are mainly influenced by municipal sewage and industrial effluent discharges, suggesting a direct influence of these sources on the pollutant distribution patterns. PAH concentrations were one to two orders of magnitude higher in comparison with those reported for riverine/estuaries systems around the world. Molecular indices, such as pyrogenic index (PI), methylphenanthrenes to phenanthrene ratio, HMW_PAH/LMW_PAH, A-PAHs/P-PAHs, FL/FL?+?PY, BaP/BaP?+?C, IP/IP?+?BgP, and Per/??(penta-aromatics) were calculated to evaluate different hydrocarbon origins and their relative importance. In general, sediments from the main basin and northwest basin of Lake Maryut showed the highest PAH concentrations with petrogenic signatures, indicating major sources of petrogenic PAHs in the city. On the other hand, lower levels of PAHs with a pyrogenic signature were widely recorded in areas that are distant from anthropogenic sources. At other locations, both petrogenic and pyrogenic inputs were significant. The concentrations of perylene relative to the penta-aromatic isomers are dominant especially in locations associated with terrestrial inputs and in the deepest core sediments, indicating diagenetic origin for the presence of perylene. Temporal trends of PAH concentrations in both cores sediments were influenced by input pathways and followed the economic development and the environmental policies of the Egyptian Government in the last 15 years. Finally, PAH levels in sediments were compared with Sediments Quality Guidelines (effects range median?Ceffects range low) for evaluation probable toxic effects on organism. Results suggest an ecotoxicological risk for benthic organisms mainly in the main basin area, where high concentrations of PAHs were found in sediments influenced by anthropogenic activities.     

Tritium radioactivity in the aquatic environment over Alexandria region,Egypt

Tritium activity is determined by standard techniques, in samples collected from fresh, marine and highly saline water around Alexandria. It has been found that, the average ³H activity is 6.32 ±1.17, 4.02±0.77 and 2.90±0.51 Bq.L^?1 for West Elnobaria Drain, Lake Marioute and Mediterranean coastal water, respectively. Tritium activity is found to be weakly correlated with water quality parameters; pH, dissolved O₂, Oxidation Reduction Potential (ORP), conductivity, salinity and chlorinity. Autocorrelation analysis indicates that the transport phenomena for ³H variations in fresh and saline water are not the same.     

Nitro-PAHs and PAHs in Atmospheric Particulate Matters and Sea Sediments in Hiroshima Bay Area, Japan

Atmospheric and sea sediment concentrations were measured for eight nitrated polycyclic aromatic hydrocarbons (nitro-PAHs) and three unsubstituted PAHs in a suburban area and sea sediments in the Hiroshima Bay watershed area, Japan, from July to December, 2006 (atmospheric particulate matter) and in September and November, 2004 (sea sediments). Atmospheric concentration was higher in winter than summer for both nitro-PAHs and PAHs. Concentrations in sea sediments were less than 10%, and pattern was similar to those of atmospheric particles. Several combustion emission sources were also measured, and the 1-NP/Pyr ratio was compared to environmental values. The ratio of atmospheric and sea sediments were significantly lower than diesel particulate matters. Further, the vehicle emission loading and sea sedimentation loading was evaluated in this watershed area, and from the comparison, the existence of other important sources PAHs were suggested.     

安徽省典型城市周边土壤-蔬菜中PAHs的污染特征

研究了安徽省合肥、芜湖和亳州市周边蔬菜地土壤和蔬菜中PAHs的含量及其污染特征。结果表明：安徽省典型蔬菜地土壤中15种PAHs（除萘外）的残留总量在58.2～437.8μg·kg-1之间,三环和四环PAHs占PAHs残留总量的70%以上。胡萝卜、菠菜和茄子体内15种PAHs的含量在23.4～209.1μg·kg-1之间,均值为120.7μg·kg-1,三环和四环PAHs占蔬菜中PAHs富集总量的92.8%～94.4%。不同蔬菜体内8种可疑性致癌PAHs的含量在11.5～17.4μg·kg-1之间,分别占蔬菜中PAHs残留总量的9.80%～13.8%,其中BaP含量在1.69～2.03μg·kg-1之间,低于国家对食品中污染物（BaP）的限量标准（5μg·kg-1）。不同类型PAHs在蔬菜体内的富集系数在0.10～9.20之间,极差达10倍以上,低分子量PAHs在蔬菜体内的富集系数要大于高分子量PAHs。不同PAHs在蔬菜体内的富集系数表现为胡萝卜〉菠菜〉茄子,其中芴在蔬菜体内的富集系数最高。     

Occurence of PAHs in Various Elements of Environment in Zabrze (Upper Silesia,Poland)

The Polycyclic Aromatic Hydrocarbons (PAHs) pollution state of the chosen town (Zabrze) of Upper Silesia, the most industrialised region in Poland, was presented. Zabrze is a town of medium size, having population twenty times bigger than a medium town polulation in Poland. In this study we determined the qualitative and quantitative composition of PAHs fraction separated from the following elements of environment: suspended dust, drinking water, soil and sewage sludge. The following analytical techniques were used: Soxhlet Extraction, Solid Phase Extraction, Gas Chromatography-Mass Spectrometry, Capillary Gas Chromatography and High Performance Liquid Chromatography. The results confirmed the significant state of examined region pollution. They stated the exceed of contents B(a)P in suspended dust. The soils in that place were heavily polluted with PAHs, about 4000 µg · kg-¹ for the sum of PAHs. The total contents of PAHs in sewage sludge of Zabrze did not exceed the analogous contents published for West European sewage sludge treatment plants and the level of determined PAHs in drinking water did not show any claims.     

珠江三角洲典型城市蔬菜中多环芳烃分布特征

在东莞市采集77个蔬菜样品,采用气相色谱-质谱仪对其16种优先控制多环芳烃(PAHs)进行分析.结果表明:东莞市蔬菜中16种PAHs含量在26.35 ～ 3748 μg/kg 之间,平均含量为656.3 μg/kg;蔬菜中PAHs含量以3环和4环PAHs为主,单个PAHs以荧蒽、芘和菲含量最高;不同种类蔬菜间PAHs含量差异很大,叶菜类较果菜类蔬菜中的PAHs含量高,主要取决于蔬菜种类间不同的生长结构特征;东莞市的蔬菜受到一定程度的PAHs污染.     

大气环境对育肥猪舍内颗粒物浓度的影响

2014年10月-2015年8月,以北京昌平某猪场3栋育肥猪舍为例,在猪舍内外设置监测点,对猪舍内外空气动力学直径≤2.5μm的颗粒物（PM2.5）、≤10μm的颗粒物（PM10）和≤100μm的颗粒物（TSP）浓度进行周年监测,并将舍外监测数据与昌平国家环境监测数据进行比较分析,以研究探讨大气环境颗粒物浓度对育肥猪舍内环境的影响。试验结果表明,试验期间舍内外PM2.5浓度的变化范围分别为23～245μgm^-3和11～372μgm^-3,PM10浓度变化范围分别为113～1182μgm^-3和25～444μgm^-3,TSP浓度变化范围分别为334～4396μgm^-3和31～742μgm^-3。育肥猪舍内PM10和TSP浓度远高于猪舍外,说明育肥猪舍内PM2.5浓度受大气环境的影响,而育肥猪舍内粒径大于2.5μm的颗粒物主要源于养殖生产活动。     

Finger-Printing Biodegradation of Petroleum Contamination in Shallow Groundwater and Soil System Using Hydro-bio-geochemical Markers and Modelling Support

This study was conducted to determine the potential of in situ biodegradation and identify the geochemical and microbial processes of the petroleum-contaminated subsurface environment using integrated hydro-bio-geochemical markers so that the risk of contamination to subsurface environment can be better understood. The contamination process and corresponding bio-geo-chemistry were analysed in parallel with geochemical and multi-variant statistical modelling at a petroleum-contaminated site in the northeast China. The total petroleum hydrocarbon analysed in the monitoring wells and soil profile demonstrated heavy contamination with potential risk to human health and eco-environment. Further detailed analysis of petroleum fractions revealed a clear spatial variation of organic compositions in groundwater. It was evident that biodegradation and preferential biodegradability contributed considerably to the fraction distribution pattern, which can also be implicated by carbon and microbial respiration in the subsurface environment. The steady decrease in SO ₄ ^2- concentration, detection of S^2-, and increase in pH and alkalinity (HCO ₃ ^- ) in groundwater during the monitoring period demonstrated that sulphate reduction was the dominant biodegradation process in most contaminated zones. The results of statistical analysis further suggested that the hydro-geochemical environment was mainly controlled by the regional hydro-geochemical and sulphate reduction process associated closely with the total petroleum hydrocarbon. Knowledge from the comprehensive study provides useful insight on fate, transport and risk assessment of the petroleum contaminants in the shallow subsurface environment.     

Quantitative Evaluation of Atmospheric Deposition Flux of Mercury in Sediments within the City of Juarez,Mexico

The city of Juarez is located in the northernpart of Mexico at the border with the United States. This reportinvestigates the mercury (Hg) contribution from atmosphericsources and its accumulation in the Juarez area estimated bymeasuring the concentration of total Hg in sediments of a smallartificial pond located within the urban area of the Juarez-ElPaso metroplex. The pond is intermittently fed by Hg-free(concentration below detection levels) groundwater from a privatewell, with sporadic input of storm overflow from a nearby watertreatment facility. Total Hg concentrations in the sedimentsvaried between 20 (detection level value) and 454 μg kg^-1 dry wt, with an average value of 202.8±153.9 μg kg^-1. Physicalcharacteristics of the sediments varied among samples, althoughnot as drastically as their Hg content did. Among the sedimentparameters, the organic matter content correlated best with theHg content. A simplified balance of total mercury supply in theaquatic system revealed a sediment Hg flux of 336.0 μg m^-2 yr^-1 and a maximum Hg atmospheric flux of 119 mg m^-2 yr^-1.Our unexpected finding of significant concentrations of Hg in thetreated wastewater and in the water column stresses the need ofcareful consideration of all possible sources in determiningmercury atmospheric deposition flux.     

Particle Phase Concentrations of Polycyclic Aromatic Hydrocarbons in the Atmospheric Environment of Jinámar,Gran Canaria

Airborne concentrations of 8 polycyclic aromatic hydrocarbons (PAHs): fluoranthene, Flt, Pyrene, Pyr, benzo(a)anthracene, BaA, chrysene, Chr, benzo(b)fluoranthene + benzo(k)fluoranthene,B(b + k)F, benzo(a)pyrene, BaP and benzo(g,h,i)perylene, B(ghi)P,were measured in Jinámar, a small town on the island of Gran Canaria (Spain) during a 12 month period (January 1995–December 1995). Concentrations ranged between 0.613 ng m^-3 for B(ghi)P and 0.040 and 0.046 ng m^-3 for pyrene and chrysene. Except for BaA all PAHs occurred at lower concentrations at temperatures below 20 °C. Relative humidity seems to influence concentrations of pyrene, chrysene, benzo(b + k)fluoranthene and benzo(a)pyrene, also affecting the latter ina different way to the other three hydrocarbons cited.     

PAHs in SD:Polycyclic aromatic hydrocarbons levels in street dust in the central area of Niterói City, RJ, Brazil

Polycyclic aromatic hydrocarbons (PAHs) were studied in street dust (SD) samples collected in the center of Niterói, a tropical city located in the State of Rio de Janeiro, Brazil, at the margins of Guanabara Bay. Sampling was carried out monthly during the year of 2002 in order to evaluate seasonal variation of PAH concentrations. Samples were extracted by ultrasonic treatment with dichloromethane, cleaned up by solid phase extraction and analyzed by gas chromatography-mass spectrometry. The concentrations of the twenty one analyzed PAHs ranged from 3.2 to 132 ng/g. Of all PAHs, pyrene, fluoranthene and naphthalene showed the highest geometric means. Total PAH concentration (σPAH) ranged from 434 to 1247 ng/g with levels of carcinogenic PAHs (σCARC) representing 29 to 45% of σPAHs. The highest value of σPAH occurred in July 2002, when the lowest temperatures were measured in the Central Area of Niterói City. σPAH and σCARC showed significant correlations with daily mean and minimum temperature, as well as with temperature during sampling, indicating that both are influenced by these parameters. The obtained results suggest that a seasonal variation of total PAH levels in SD may occur in the studied area.     

固原市原州区生态环境与经济系统的耦合协调发展

[目的]构建宁夏回族自治区固原市原州区生态环境系统和社会经济系统之间的耦合度和耦合协调度模型,以期为区域的协调发展调控提供科学依据。[方法]基于固原市原州区2002—2016年生态环境和社会经济的数据,构建原州区区域生态系统指标评价体系,采用熵值赋权法计算各个评价指标的权重以及综合评价指数,通过建立耦合度、耦合协调度模型和灰色预测度模型,得到并预测该区域生态环境系统和社会经济系统的耦合度和耦合协调度发展趋势以及耦合协调类型。[结果] 2002—2016年,固原市原州区社会经济系统评价指数稳定上升,受生态环境压力的影响,生态系统综合评价指数呈现先下降后波动上升的趋势,前者的发展速度快于后者;耦合度和耦合协调度不断上升,耦合协调类型从经济滞后中度失调型发展为生态环境滞后的濒临失调型;通过模型预测,2017—2025年生态环境系统和社会经济系统之间耦合度及耦合协调度将逐渐升高,耦合协调类型会不断向理想状态发展。[结论]固原市原州区由于经济发展水平快于生态环境建设力度,从而制约了该区域整体的协调发展。因此为实现原州区区域生态系统的可持续发展。还需大力加强对生态环境的建设。     

土壤环境中多环芳烃的微生物降解及联合生物修复

研究土壤环境中持久性有机污染物的生物降解及其生物修复技术是当今国际环境修复科学技术前沿领域的重要课题。本文重点论述了土壤环境中持久性有机污染物多环芳烃的微生物降解机理及其在生物修复中的应用等,并结合当前研究进展,展望了基于多种修复措施相结合的多环芳烃污染土壤联合生物修复工程技术的开发与应用前景。     

苏州市酸雨特征及其与大气环境的关系分析

为了解苏州市酸雨现状及其与大气环境的关系,应用统计分析、相关分析和数值模拟等方法对352个酸雨观测样本进行分析研究。结果表明:352个酸雨观测样本中,平均pH值4.5;pH值>5.6的非酸雨所占比例仅8%,其余92%为酸雨,pH值<4.5的强酸雨出现频率高达67%;pH年均值变化不大,存在一定的月际差异;电导率K值在11.9～284μS.cm-1间剧烈变动,表明大气降水中离子总量差别很大;不同降雨强度时,pH值、K值存在明显差别:大雨和暴雨逢雨必酸,小雨和中雨少数样本pH值>5.6,为非酸雨;K值随雨量增大而减小,说明小雨滴对大气环境中污染物的吸附作用更明显;pH值与大气污染物SO2、NO2、PM10、PM2.5质量浓度负相关;选取了2010年3月一次酸雨过程应用数值模拟方法模拟北方沙尘水平和垂直传输路径,印证了大气中污染物质可以远距离传播,沙尘中离子成分含量高,可导致降雨K值增大,酸度降低。     

慈溪市蔬菜地分等及环境质量评价

通过对慈溪市蔬菜地土壤肥力与环境质量调查及分析,对慈溪市蔬菜地进行了分等与评价,结果显示,该市蔬菜地重金属与有机氯农药含量均低于国家标准,符合建立无公害蔬菜地要求。按照国家农业行业标准蔬菜地分等进行评价,10个点中有9个定为三等,1个定为四等。     

玉溪市土地利用对生态环境的影响研究

从城市土地利用的结构、布局和强度阐述了玉溪市土地利用变化的特征,并探讨了土地利用带来的系列生态环境效应,结果表明:玉溪市土地开发强度大,已利用土地比例高;土地利用结构与布局不尽合理;近年来伴随城市发展,环境污染状况与区域土地利用状况存在密切关系,大气、水、土壤污染呈现加重趋势,成为影响玉溪市可持续发展的主要环境问题.     

新疆克拉玛依市兴农湖剖面古沉积环境分析

粒度是沉积物中各种粗细颗粒的机械组成,可以用于沉积环境类型的识别和物质运动方式的判定。通过对克拉玛依市兴农湖剖面的粒度数据测量分析,判定该地区沉积物为湖相沉积。联系周围区域构造形态,该地区应为古玛纳斯湖的湖盆地区。     

吐鲁番市城市化与生态环境动态分析

通过构建城市化综合指数与生态环境综合指数的指标体系,利用变异系数法确定各个指标的权重,借助加权求和对吐鲁番市2000—2008年的城市化与生态环境的综合指数给予量化分析,结果表明:两者均呈现上升趋势,尽管生态环境综合指数波动比较显著。结合GM(1,1)模型对吐鲁番市城市化与生态环境的综合指数进行预测,预测等级均为好,对实际有一定的参考价值,同时城市化的增速快于生态环境;应用关联度知识,对吐鲁番市连续9a不同的年份进行分析发现,随着时间的推移,城市化与生态环境综合指数的关联度逐渐增加,依次为0.600 7,0.621 5,0.669 6,由此可以说明吐鲁番市城市化与生态环境的联系将越来越紧密,而且逐年增强。     

The Contribution to Nitrogen Deposition and Ozone Formation in South Norway from Atmospheric Emissions Related to the Petroleum Activity in the North Sea

A photochemical puff-trajectory model (Fotoplume) has been applied to simulate emissions, atmospheric transport and chemical transformations of pollutants from offshore oil and gas production in the North Sea. The above model was used in conjunction with the European Monitoring and Evaluation Programme (EMEP) regional Lagrangian oxidant model. The Fotoplume and EMEP models were used to evaluate the effects of the atmospheric emissions from the oil and gas exploration activity in the Norwegian sector of the North Sea. Deposition of nitrogen and formation of boundary level ozone in Southern Norway due to North Sea emissions of nitrogen oxides (NO_x), carbon monoxide (CO) and volatile organic compounds (VOC) have been studied. The petroleum activity in the North Sea is calculated to contribute approximately 20% of the nitrogen deposition in the coastal areas of Norway in 1992. In addition, the models were used to estimate the AOT40 ozone exposure levels. The results indicate that emissions from British and Norwegian oil and gas exploitation sector separately contribute to less than 5% each of the AOT40 values for coniferous forests and meadows. Comparison of model calculations with experimental measurements is quite satisfactory and the models show realistic results for both the nitrogen deposition and AOT40 values.